Switching unit for controlling an electronically commuted ventilation motor

摘要

The unit has a power stage (3) for controlling windings of an electronically commutated fan motor (2). A control stage (4) controls the power stage. An operating voltage (Vs) of the control stage is separated from an operating voltage (Vl) of the power stage by a diode (D1). A smoothing circuitry i.e. low-pass filter, smoothens the operating voltage of the control stage and comprises a resistor (R1) coupled to a capacitor (C1). Another diode (D2) is provided as a polarity inversion protection between the operating voltage of the power stage and an operating voltage (V) of the circuit unit. An independent claim is also included for a fan module for an electronic device, including a switching element.